Epoxy woes

[ChrisVZ]

Having issues with bubbles in my epoxy. I built my bar top from oak, and assumed that 2 coats of polyurethane would sufficient to seal the pores in the wood before applying the epoxy. I was wrong and the wood is releasing a lot of bubbles from the grain. I have been trying to stay on top of them with a heat gun, but it seems that every time I heat it, twice the number of bubbles replace the ones I just popped.
I am thinking I can save it by continuing to hit them with the heat until the epoxy sets up enough to seal the grain, and then pouring a second coat to fill in the dimples that they leave. Anyone have any other tips or pointers that can help me save my work?

 

[raysmithtx]

In my experience a heat gun will blow dust motes all over the finish. A propane torch or even a torch lighter works best. The heat gun also heats up too large an area and releases more bubbles. You will probably end up putting another coat of epoxy on after it dries and you lightly sand it with some 220 grit paper. Sponge brush works best. I work with epoxy just about every day.

 

[ChrisVZ]

I do have a propane torch, but it keeps going out when I aim it down at the surface. That's why I grabbed the heat gun. Will have to get a new torch nozzle before I try this.
The epoxy I am using claims 72 hours to cure. Do you usually wait longer than that to sand, or will I be good at 72?

 

[raysmithtx]

I work with commercial epoxy and it cures in four hours but I wait 24 hours to sand. If you sand too soon you will clog the sandpaper. I have an attachment on my propane tank that lets me move the flame around without moving the tank. HD and Lowes sell them but for a small job you can get the tank to.work. Use very low heat for the bubbles. Very low. High heat will just create more work and bubbles. Epoxy is a very forgiving product so you will be able to get a great finish.

 

[ChrisVZ]

Epoxy is a very forgiving product so you will be able to get a great finish.

I hope so. Not only is oak expensive, but I have a lot of work in on it and it was looking great before the epoxy.

 

[raysmithtx]

I should have mentioned earlier that the biggest problem I have seen is people applying epoxy at too low a temperature. Be sure the epoxy and the wood is at least at the minimum temp. shown on the container. The wood should be kept above the min. Temp. While it cures. If you don't you can end up with lots of bubbles. If the epoxy has bubbles it it after you mix it, then the temp. is too low. It should be fairly clear after you thoroughly mix the two parts.

 

[ChrisVZ]

I applied another coat last night, and I think it turned out well. There are some tiny flaws caused by the bubbles in the first coat, but overall, I am happy with the results.
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